22 results on '"Ling You"'
Search Results
2. Distinct Lymphocyte Immunophenotyping and Quantitative Anti-Interferon Gamma Autoantibodies in Taiwanese HIV-Negative Patients with Non-Tuberculous Mycobacterial Infections
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Wen-I. Lee, Yao-Fan Fang, Jing-Long Huang, Huey-Ling You, Meng-Ying Hsieh, Wan-Ting Huang, Chi-Jou Liang, Chen-Chen Kang, and Ting-Shu Wu
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Immunology ,Immunology and Allergy - Published
- 2023
3. Plant growth regulators improve nitrogen metabolism, yield, and quality of soybean–rhizobia symbiosis
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Wenhao Chen, Juan Li, Huawei Yuan, Ling You, Qin Wei, Ruizhang Feng, Sipei Jiang, and Xiaohong Zhao
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Applied Microbiology and Biotechnology - Abstract
Purpose In recent years, considerable research has been conducted on the use of plant growth regulators (PGRs) to improve crop yields. Large amounts of PGRs are applied to regulate crop growth. However, few studies have assessed the impact of PGRs, which leave soil residues, on soil microorganisms, especially rhizobia. Methods In this study, the influence of inoculation of soybean roots with Sinorhizobium fredii and Bradyrhizobium japonicum exposed to gibberellin A3 (GA3) and mepiquat chloride (MC) on nodule number, nitrogenase activity, and a symbiotic nitrogen fixation gene (fixA) expression was studied. The nitrate content, free amino acids, and nitrate reductase activity of the roots, and seed yield and quality of soybean were measured. Result Nodulation was promoted to some extent, whereas nitrogenase activity and fixA expression were inhibited to some extent by treatment with GA3; however, these effects were reversed by treatment with MC. In a pot experiment to study phenotypic characteristics, rhizobia treatment in combination with GA3 or MC significantly improved soybean yield and seed nitrogen content, and increased the root nitrate content, free amino acid content, and nitrate reductase activity. Conclusion The results indicated that PGRs, which leave soil residues, have significant positive effects on the growth and activity of soybean and rhizobia.
- Published
- 2023
4. The effect of different preoperative left atrial appendage emptying speeds on left atrial function in patients with persistent atrial fibrillation after left atrial appendage closure combined with catheter ablation
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Chao, Yang, Jing, Yang, Qian, Liu, Ling, You, Jinglan, Wu, Yanan, Zhang, Lianxia, Wang, and Ruiqin, Xie
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Atrial Fibrillation ,Catheter Ablation ,Humans ,Atrial Appendage ,Atrial Function, Left ,Cardiac Surgical Procedures ,Cardiology and Cardiovascular Medicine - Abstract
Objective The present study aimed to investigate whether different preoperative left atrial appendage emptying speeds (LAAEVs) have an effect on left atrial function in patients with sinus arrhythmia after left atrial appendage closure (LAAC) combined with catheter ablation (CA). Methods A total of 163 patients with persistent non-valvular atrial fibrillation who received combined LAAC+CA surgery were included in the present study. Regular follow-up was conducted for 12 months, and patients with complete data and successful sinus rhythm recovery were selected as the study subjects (n = 82). The patients were divided into two groups: the LAAEV n = 41 each). The propensity score was used for matching according to gender, age, CHA2DS2-VASc score, and HAS-BLED score. The changes in the two groups in LA structure, storage function, conduit function, and pump function were compared. Results Before surgery, the maximum LA volume (LAVmax) and minimum LA volume (LAVmin) were greater in the LAAEV Conclusion Before combined LAAC+CA surgery, the LA structure and function of the LAAEV
- Published
- 2022
5. Move Analysis of the Literature Review Chapters in Taiwanese Graduate Students’ TESOL Theses and Dissertations
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Ming-Cheng Li and Yu-ling You
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Linguistics and Language ,Graduate students ,Field (Bourdieu) ,Rhetorical question ,Mathematics education ,Language education ,Discourse community ,Sociology ,Doctoral dissertation ,Curriculum ,Education ,Task (project management) - Abstract
Literature Review (LR) is essential in research articles (RAs) but EFL learners often find writing LR a difficult task (e.g., [1]; [2]; [3]; [4]). Among the often-reported difficulties, how to organize an LR chapter is one of the main challenges (e.g., [5]; [6]). This paper thus aims to examine the rhetorical structures of the LR chapters in both master’s theses and doctoral dissertations written by the EFL learners in Taiwan. The purpose is to investigate how the authors organize the LR chapters in terms of move and step ([7]; [8, 9]) and if experiences of writing RAs have impacts on the use of move, i.e., on how the EAP writers organize the rhetorical structures of LR chapters. The findings of examining 20 master’s thesis and 20 doctoral dissertation LR chapters in the field of TESOL show the two groups of authors organized the LR chapters in a similar way. We claim that the master’s thesis and doctoral dissertation authors acquired the rhetorical structures and writing conventions of the TESOL discourse community through instructions, training, and experiences. The findings provide further supports to the notions of discourse community and shared writing conventions and to the needs of including the genre knowledge in EAP learners’ writing curriculum.
- Published
- 2021
6. Effects of a quasi-experimental study of using flipped classroom approach to teach evidence-based medicine to medical technology students
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Steve Leu, Chia-Pei Chou, Hsien-Li Huang, Huey-Ling You, Chih-Hung Chen, and Mao-Meng Tiao
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Male ,Evidence-based medicine ,020205 medical informatics ,Quasi-experiment ,Taiwan ,lcsh:Medicine ,02 engineering and technology ,Flipped classroom ,Education ,Education, Distance ,Young Adult ,Medical Laboratory Personnel ,Quasi experimental study ,Medical technology ,ComputingMilieux_COMPUTERSANDEDUCATION ,0202 electrical engineering, electronic engineering, information engineering ,eBook ,Humans ,lcsh:LC8-6691 ,Class (computer programming) ,Medical education ,lcsh:Special aspects of education ,Fresno test ,Teaching ,lcsh:R ,05 social sciences ,050301 education ,Health technology ,Problem-Based Learning ,General Medicine ,Test (assessment) ,Female ,Research Object ,Psychology ,0503 education ,Research Article - Abstract
Background Flipped classroom is known to improve learning efficiency and to develop one’s ability to apply high-level knowledge. To investigate the effect of flipped classroom approach on teaching evidence-based medicine to medical technology students, we conducted a tailor-made six flipped classroom based EBM courses for medical technology students. Methods This study adopted a qusai-experimental design with 62 medical technology interns as the research object. Students in the experimental group attended the flipped classroom course, while students in the control group attended the traditional course. The learning outcomes were evaluated by Fresno test in both groups. Furthermore, to understand student’s perceptions on the flipped classroom approach, students in the experimental group were required to fill in a satisfaction survey and answer some open-ended questions. Results The Fresno test scores of the experimental group were significantly higher than that of the control group. From the results of the satisfaction survey, we know that students were satisfied with this course format. Students claimed that the flipped classroom approach could improve their learning efficiency and the interactions with teacher could help them to think more deeply. Conclusions To conclude, most students showed positive attitudes and views on flipped classroom strategy. Moreover, students’ questions were solved more effectively during class resulting in an improvement of effectiveness of evidence-based medicine trainings.
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- 2020
7. Effects of different ablation strategies on long-term left atrial function in patients with paroxysmal atrial fibrillation: a single-blind randomized controlled trial
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Jinglan Wu, Ying Yang, Chenfeng Zhang, Ling You, Lixia Yao, Guangli Yin, Bolun Zhou, Honglin Yin, Ruiqin Xie, Li-Li Jin, and Yue Liu
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Male ,0301 basic medicine ,medicine.medical_specialty ,Systole ,medicine.medical_treatment ,Diastole ,lcsh:Medicine ,Cryosurgery ,Article ,Pulmonary vein ,law.invention ,03 medical and health sciences ,Imaging, Three-Dimensional ,0302 clinical medicine ,Randomized controlled trial ,Recurrence ,law ,Internal medicine ,Atrial Fibrillation ,medicine ,Humans ,Single-Blind Method ,Sinus rhythm ,lcsh:Science ,Aged ,Multidisciplinary ,business.industry ,lcsh:R ,Atrial fibrillation ,Cryoablation ,Middle Aged ,medicine.disease ,Ablation ,Treatment Outcome ,030104 developmental biology ,Surgery, Computer-Assisted ,Echocardiography ,Pulmonary Veins ,Outcomes research ,Catheter Ablation ,Cardiology ,Female ,lcsh:Q ,business ,Interventional cardiology ,030217 neurology & neurosurgery - Abstract
Restoration of sinus rhythm in atrial fibrillation (AF) by radiofrequency catheter ablation (RFCA) is associated with a transient stunning of left atrial (LA) function. However, the long-term effects of different ablation strategies on LA function remain undetermined. We performed randomized controlled trial to evaluate the effects of RFCA, cryoablation, and 3D mapping-guided cryoablation on LA function of proximal AF patients within 1 year. The 3D mapping-guided cryoablation was defined as a maximum of two cryoablation procedures for each pulmonary vein accompanied by RFCA for additional points until complete pulmonary vein isolation was achieved. Conventional and speckle tracking echocardiographic analyses were performed to evaluate LA function. Among the 210 patients (70 in each group) included, a trend of decreasing LA systolic and diastolic function was observed in all groups, as evidenced by decreases in peak A-wave velocity, the global LA peak systolic strain, the peak strain rate, the peak early diastolic strain rate, and the peak late diastolic strain rate within 7 days to 3 months after ablation followed by gradual recovery thereafter. However, the temporal changes in the above four strain parameters among the three groups did not differ significantly within 1 year after ablation (all p > 0.05). Parameters of the LA emptying fraction and LA dimensions were not significantly affected. These results suggested that stunning of LA function occurred within 7 days to 3 months after ablation, and different strategies of AF ablation did not differentially affect the temporal changes in LA function up to 1 year after ablation.
- Published
- 2019
8. Cyclic GMP-dependent protein kinase II is necessary for macrophage M1 polarization and phagocytosis via toll-like receptor 2
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Shun-Jen Chang, Chung-Jen Chen, Huey-Ling You, Jan-Gowth Chang, Changgui Li, and Wei-Ting Liao
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Lipopolysaccharides ,Toll-like receptor ,Chemokine ,Gene knockdown ,biology ,Chemistry ,Macrophages ,Phagocytosis ,Cyclic GMP-Dependent Protein Kinase Type II ,Models, Biological ,Toll-Like Receptor 2 ,Uric Acid ,Cell biology ,TLR2 ,Gene Expression Regulation ,Drug Discovery ,Immunology ,biology.protein ,TLR4 ,Humans ,Molecular Medicine ,CXCL10 ,Macrophage ,Genetics (clinical) - Abstract
Cyclic GMP-dependent protein kinase II (cGKII; PRKG2) phosphorylates a variety of biological targets and has been identified as a gout-susceptible gene. However, the regulatory role of cGKII in triggering gout disease has yet to be clarified. Thus, we plan to explore the specific function of cGKII in macrophages related to gout disease. By using cGKII gene knockdown method, we detected macrophage M1/M2 polarization, phagocytosis, and their responses to stimulation by monosodium urate (MSU). cGKII was highly expressed in M1 phenotype, but not in M2, and cGKII knockdown significantly inhibited macrophage M1 polarization by decreasing M1 chemokine markers (CXCL10 and CCL2) and downregulating phagocytosis function. We further identified that cGKII-associated phagocytosis was mediated by upregulating toll-like receptor 2 (TLR2) expression, but not by TLR4. Mimicking gout condition by MSU treatments, we found that MSU alone induced cGKII and TLR2 expression with increased M1 polarization markers and phagocytosis activity. It means that cGKII knockdown significantly inhibited this MSU-induced cGKII-TLR2-phagocytosis axis. Our study showed that cGKII plays a key role in M1 polarization, especially in TLR2-mediated phagocytosis under MSU exposure. The findings provide evidence for the possible role of cGKII as an inflammation exciter in gout disease.Gout-susceptible gene cGKII is necessary for macrophage M1 polarization. cGKII regulates M1 phagocytosis function via TLR2. Monosodium urate treatments increase cGKII expression and related function. This study reveals the role of cGKII in enhancing gouty inflammatory responses.
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- 2014
9. An integrated microfluidic system for live bacteria detection from human joint fluid samples by using ethidium monoazide and loop-mediated isothermal amplification
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Shu Ling Chen, Chih-Hung Wang, Jiunn Jong Wu, Gwo-Bin Lee, Ting Hang Liu, Huey Ling You, Mel S. Lee, and Wen Hsin Chang
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0301 basic medicine ,Detection limit ,030222 orthopedics ,Lysis ,biology ,Chemistry ,030106 microbiology ,Microfluidics ,Loop-mediated isothermal amplification ,Molecular Diagnostic Method ,Computational biology ,Condensed Matter Physics ,Molecular diagnostics ,biology.organism_classification ,Molecular biology ,Electronic, Optical and Magnetic Materials ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Materials Chemistry ,DNA ,Bacteria - Abstract
Periprosthetic joint infection (PJI) is one of the severe complications of prosthetic joint replacement. Delayed PJI diagnosis may anchor bacteria in periprosthetic tissues, and removal of the prosthesis might be inevitable. The diagnosis of PJI depends on the identification of microorganisms by standard microbiological cultures or more advanced molecular diagnostic methods for detection of bacterial genes. However, these methods are relatively time-consuming, labor-intensive and not human error-free. Moreover, it is challenging to distinguish live from dead bacteria by using DNA-based molecular diagnostics since bacterial DNA will be remained in the tissue even after the death of the bacteria. In this work, an integrated microfluidic system has been developed to perform the entire molecular diagnostic process for the PJI diagnosis in a single chip. We combined the loop-mediated isothermal amplification (LAMP) with ethidium monoazide (EMA) in an integrated microfluidic system to identify live bacteria with reasonable sensitivity and high specificity. All the diagnostic processes including bacteria isolation, cell lysis, DNA amplification and optical detection can be automatically performed on the integrated microfluidic system by using a compact custom-made control system. The integrated system can accommodate four primers complementary to six regions of the target genes and improve the detection limit by using LAMP. The limit of detection in this multiple EMA-LAMP assay could be as low as 5 fg/reaction (~1 CFU/reaction) when choosing an optimized primer set as we demonstrated in mecA gene detection. Thus, the developed system for PJI diagnosis has great potential to become a point-of-care device.
- Published
- 2017
10. High levels of serum β2-microglobulin predict severity of coronary artery disease
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Haijuan Hu, Ruiqin Xie, Wei Cui, Ximiao He, Hongmei Zheng, Jidong Zhang, Guoqiang Gu, Xiaohong Yang, and Ling You
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Male ,China ,medicine.medical_specialty ,Coronary Artery Disease ,030204 cardiovascular system & hematology ,Coronary Angiography ,Severity of Illness Index ,Severity ,Coronary artery disease ,03 medical and health sciences ,0302 clinical medicine ,Predictive Value of Tests ,Internal medicine ,Severity of illness ,Prevalence ,medicine ,Humans ,cardiovascular diseases ,030212 general & internal medicine ,Risk factor ,β2-Microglobulin ,Aged ,Framingham Risk Score ,Receiver operating characteristic ,business.industry ,Case-control study ,Odds ratio ,Middle Aged ,Prognosis ,medicine.disease ,Confidence interval ,Up-Regulation ,ROC Curve ,Area Under Curve ,Case-Control Studies ,Cardiology ,Female ,beta 2-Microglobulin ,Cardiology and Cardiovascular Medicine ,business ,Biomarkers ,Research Article - Abstract
Background The identification of new risk factors for coronary artery disease (CAD) is increasingly sought in an effort to tackle this threatening disease. β2-microglobulin (B2M) is reported to associate with peripheral arterial disease and adverse cardiovascular outcomes. However, the association between B2M and cardiovascular disease remains under-researched. This study evaluated the effects of B2M on CAD without renal dysfunction. Methods One thousand seven hundred sixty-two subjects (403 non-CAD subjects and 1,359 CAD subjects) were investigated. Fasting samples were collected to determine B2M level. The Gensini and SYNTAX scores were used to assess the severity of CAD. Results CAD subjects were significantly higher in serum B2M level comparing with non-CAD subjects (1.25 ± 0.46 vs 1.14 ± 0.28 mg/L, p
- Published
- 2017
11. Vimentin Regulates Neuroplasticity in Transected Spinal Cord Rats Associated with micRNA138
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Ling You, Bao-Jiang Qian, Yuan Zhang, Jia Liu, Yun Hui Zhang, Fei-Fei Shang, Ping Dai, Na Lin, Ran Liu, Yang Xu, Mu He, and Ting-Hua Wang
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Male ,Pathology ,medicine.medical_specialty ,Molecular Sequence Data ,Neuroscience (miscellaneous) ,Vimentin ,macromolecular substances ,Biology ,Rats, Sprague-Dawley ,Cellular and Molecular Neuroscience ,Downregulation and upregulation ,microRNA ,medicine ,Animals ,Spinal cord injury ,Cells, Cultured ,Spinal Cord Injuries ,Gene knockdown ,Neuronal Plasticity ,Base Sequence ,Microarray analysis techniques ,Spinal cord ,medicine.disease ,Rats ,Astrogliosis ,Cell biology ,MicroRNAs ,medicine.anatomical_structure ,Animals, Newborn ,Neurology ,biology.protein ,Female - Abstract
Spinal cord injury (SCI) often results in motor disability concomitant with limit neuroplasticity; the underlying mechanism, however, is still unclear. This study established spinal cord transection rats model (T10), then performed cDNA microarray analysis and found that vimentin located in astrocytes was increased significantly in scar tissues after transection. To understand the role of vimentin and it's mechanism of regulation, RNA interference and luciferase assay were used. Vimentin knockdown in the scar tissues showed a significant improvement on locomotor function in hindlimbs, while vimentin overexpression exhibited an opposite effect. In vitro, vimentin downregulation or overexpression can effectively inhibit or increase astrogliosis, respectively. Moreover, by using biological informatics technology, we predicted that vimentin may be as the target of micRNA138 (miR-138), and confirmed that miR-138 could regulate vimentin by luciferase activity assay. The present results not only validated the exact role of vimentin in transected spinal cord, but also exhibited a novel regulation mechanism, in which miR-138 may regulate vimentin to promote neuroplasticity. It, therefore, provides a novel target for gene drug discovery based on miRNA-138 or vimentin for the treatment of SCI in the future clinic trial.
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- 2014
12. Large-scale somatic embryogenesis and regeneration of Panax notoginseng
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Xiang Ling You, Yuhua Li, Xiao Tan, Jin Ling Dai, and Yong Eui Choi
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Somatic embryogenesis ,biology ,Somatic cell ,Embryo ,Horticulture ,biology.organism_classification ,chemistry.chemical_compound ,Murashige and Skoog medium ,chemistry ,Callus ,Shoot ,Botany ,Panax notoginseng ,Gibberellic acid - Abstract
An efficient system for inducing somatic embryogenesis in Panax notoginseng was established using shaker flasks and bioreactor cultures; furthermore, regenerated plantlets were successfully transferred to ex vitro soil conditions. Embryogenic callus was induced from segments of adventitious roots incubated on Murashige and Skoog (MS) medium containing 1.0 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D) after 5 weeks of culturing. The highest frequency (100%) of somatic embryogenesis, with a mean of 32.7 somatic embryos per callus, was obtained on embryogenic callus incubated on a medium containing 0.5 mg/L 2,4-D. To scale-up somatic embryo formation, 10 g (~1.65 × 104) of early globular-stage somatic embryos were incubated in a 3 L airlift bioreactor containing 1.5 L 1/2 MS medium without plant growth regulators (PGRs) for a period of 4 weeks; these globular-stage somatic embryos then developed into cotyledonary embryos. When maintained on PGR-free medium, the cotyledonary embryos developed roots but did not develop shoots. However, when they were treated with gibberellic acid (GA3), they continued to germinate and transformed into plantlets after 2 weeks of culture. Plantlets with well-developed shoots and roots were transferred to an autoclaved vermiculite and perlite mixture, acclimatized for a period of 3 months and successfully transferred to forest mountain soil. Following overwintering, these plants produced new growth.
- Published
- 2011
13. The role of high-sensitivity C-reactive Protein, interleukin-6 and cystatin C in ischemic stroke complicating atrial fibrillation
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Jiagao Lv, Peihua Wang, Katherine Cianflone, Ling You, Dao Wen Wang, and Chunxia Zhao
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Male ,medicine.medical_specialty ,Biomedical Engineering ,Biochemistry ,Brain Ischemia ,Biomaterials ,Brain ischemia ,Predictive Value of Tests ,Risk Factors ,Internal medicine ,Atrial Fibrillation ,Genetics ,medicine ,Humans ,cardiovascular diseases ,Cystatin C ,Risk factor ,Interleukin 6 ,Stroke ,Aged ,Earth-Surface Processes ,biology ,Interleukin-6 ,business.industry ,C-reactive protein ,Case-control study ,nutritional and metabolic diseases ,Atrial fibrillation ,Middle Aged ,medicine.disease ,C-Reactive Protein ,Case-Control Studies ,biology.protein ,Cardiology ,Female ,business - Abstract
This study examined the role of high-sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6) and cystatin C in ischemic stroke complicating atrial fibrillation (AF) and the relationship of systemic inflammation with this disease in order to identify AF patients who are at high risk of stroke and need optimal anticoagulant therapy. A total of 103 AF patients, simple (n=75) or complicated by ischemic stroke (n=28), and 112 control subjects were recruited. IL-6 level was detected by using enzyme linked immunosorbent assay. Cystatin C and hsCRP levels were measured by means of a particle-enhanced immunonephelometric assay. The results showed that the AF patients had higher levels of hsCRP (P=0.004), IL-6 (P=0.000), and cystatin C (P=0.000) than control subjects. Plasma hsCRP level was increased in the AF patients with ischemic stroke as compared to the patients with simple AF (P=0.036). The AF patients who had the level of hsCRP exceeding 3.83 mg/L were at a higher risk than those with hsCRP level lower than 3.83 mg/L (P=0.030). After adjusting for other factors, cystatin C remained positively associated with IL-6 (r=0.613) and hsCRP (r=0.488). It was concluded that hsCRP is positively correlated with ischemic stroke complicating AF and may be a risk factor independent of other risk factors for AF. Elevated cystatin C level is also indicative of the increased risk of AF.
- Published
- 2010
14. Plasmolysis treatment enhances the expression of callose synthase gene in zygotic embryos of Eleutherococcus senticosus
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Hu Xilin, Xiang-ling You, Yan An, and De-an Xia
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Epidermis (botany) ,Somatic embryogenesis ,Somatic cell ,Eleutherococcus senticosus ,Callose ,Forestry ,Biology ,Molecular biology ,Plasmolysis ,chemistry.chemical_compound ,chemistry ,medicine ,Mannitol ,Explant culture ,medicine.drug - Abstract
In previous study we reported that pretreatment with plasmolysis enhanced somatic embryo formation in hypocotyls of Eleutherococcus senticosus. In the present study, the expression level of callose synthase gene in embryos of E. senticosus in response to 2,4-D, sucrose and mannitol treatments was analyzed by RT-PCR. The results show that plasmolysis pretreatment using sucrose and mannitol significantly promoted the expression of callose synthase gene. Also, the thicker cell walls of explant plasmolyzed compared with controls were observed during the somatic embryogenesis. We suggest that the callose may make the cells in epidermis separate from neighboring cells and then develop into embryogenic potential cells.
- Published
- 2010
15. Plant regeneration via direct somatic embryogenesis in Panax japonicus
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Jung Yeon Han, Yong-Eui Choi, and Xiang Ling You
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animal structures ,food.ingredient ,Somatic embryogenesis ,Somatic cell ,Embryogenesis ,food and beverages ,Embryo ,Plant Science ,Biology ,Andrology ,Murashige and Skoog medium ,food ,embryonic structures ,Botany ,Subculture (biology) ,Cotyledon ,Biotechnology ,Explant culture - Abstract
Panax japonicus is one of the important medicinal plants. Here, we established the protocol for plant regeneration of P. japonicus via direct somatic embryogenesis. Somatic embryos were directly obtained from the segments of zygotic embryos on MS medium with 4.4 μM 2,4-D. Thereafter, somatic embryos were produced by repetitive secondary somatic embryogenesis. The secondary somatic embryo formation was enhanced by plasmolyzing pretreatment (1.0 M mannitol for 10 h). Frequency of secondary somatic embryo formation from cotyledon segments was lowered by plasmolyzing pretreatment, but the number of somatic embryos per explants was greatly increased. Plasmolyzing pretreatment resulted in retardation of embryo growth and required subculture to fresh medium for further growth of embryos into cotyledonary stage. Without plasmolyzing pretreatment, cotyledonary embryos were obtained after 8 weeks of culture. All the cotyledonary somatic embryos germinated by 5 μM GA3 treatment, but only 15.3% were germinated on hormone-free medium. After 2 months of culture on 1/2 strength WPM medium, plantlets produced flowers spontaneously. In the anthers of in vitro flowers, microsporogenesis occurred normally with low number of pollen grains.
- Published
- 2007
16. Cellular change and callose accumulation in zygotic embryos of Eleutherococcus senticosus caused by plasmolyzing pretreatment result in high frequency of single-cell-derived somatic embryogenesis
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Yong Eui Choi, Xiang Ling You, and Jae Seon Yi
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Sucrose ,animal structures ,Somatic embryogenesis ,Cell ,Embryonic Development ,Eleutherococcus ,Plant Science ,Biology ,Plasmolysis ,Plant Epidermis ,Cell wall ,chemistry.chemical_compound ,medicine ,Mannitol ,Glucans ,Eleutherococcus senticosus ,Callose ,Embryogenesis ,Embryo ,Cell Biology ,General Medicine ,Hypocotyl ,Cell biology ,medicine.anatomical_structure ,Biochemistry ,chemistry ,Seeds ,embryonic structures - Abstract
Eleutherococcus senticosus zygotic embryos were pretreated with 1.0 M mannitol or sucrose for 3-24 h. This pretreatment resulted in a high frequency of somatic-embryo formation on hormone-free medium. All the somatic embryos developed directly and independently from single epidermal cells on the surface of zygotic embryos after plasmolyzing pretreatment. Scanning electron microscopic observation revealed that the epidermal cells of hypocotyls rapidly became irregular and showed a random orientation before somatic-embryo development commenced. At the same time, the epidermal cells in the untreated control remained regular. Callose concentration determined by fluorometric analysis increased sharply in E. senticosus zygotic embryos after plasmolyzing pretreatment but remained low in the untreated control. Aniline blue fluorescent staining of callose showed that the plasmolyzing pretreatment of zygotic embryos resulted in heavy accumulation of callose between the plasma membrane and cell walls. On the basis of these results, we suggest that plasmolyzing pretreatment of zygotic embryos induces the accumulation of callose, and the interruption of cell-to-cell communication imposed by this might stimulate the reprogramming of epidermal cells into embryogenically competent cells and finally induce somatic-embryo development from single cells.
- Published
- 2006
17. Overexpression of tumor susceptibility gene TSG101 in human papillary thyroid carcinomas
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Chih-Chi Andrew Hu, Fang-Ping Chao, Rue-Tsuan Liu, Fong-Fu Chou, Huey-Ling You, Chao-Cheng Huang, Jiin-Tsuey Cheng, and Ching-Mei Chen
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Transcriptional Activation ,Cancer Research ,endocrine system diseases ,macromolecular substances ,In situ hybridization ,medicine.disease_cause ,Loss of heterozygosity ,Downregulation and upregulation ,Antibody Specificity ,Genetics ,medicine ,Humans ,TSG101 ,Neoplastic transformation ,RNA, Neoplasm ,Thyroid Neoplasms ,Molecular Biology ,In Situ Hybridization ,Endosomal Sorting Complexes Required for Transport ,biology ,TSG101 Gene ,Reverse Transcriptase Polymerase Chain Reaction ,Immunohistochemistry ,Molecular biology ,Carcinoma, Papillary ,Up-Regulation ,DNA-Binding Proteins ,Mutation ,biology.protein ,Cancer research ,Mdm2 ,Carcinogenesis ,Transcription Factors - Abstract
Functional inactivation of tumor susceptibility gene tsg101 leads to cellular transformation and tumorigenesis in mice. While human TSG101 is located in a region where frequent loss of heterozygosity can be detected in a variety of cancers, no genomic deletion in TSG101 gene has been reported, casting a doubt on the role of TSG101 as a classical tumor suppressor. Some studies have revealed that TSG101 is a frequent target of splicing defects, which correlate with cellular stress and p53 status. Furthermore, recent reports have identified TSG101 as a part of the MDM2/p53 regulatory circuitry, a well-recognized circuitry that upon deregulation results in tumorigenesis. Interestingly, overexpression of tsg101 from an adventitious promoter also leads to neoplastic transformation. On the basis of this information, we have analysed TSG101 gene expression in 20 human papillary thyroid carcinomas (PTCs) by immunohistochemistry and demonstrated that the overexpression of TSG101 protein is closely associated with human PTCs. Further sequence analysis reveals no mutation in cDNA region encoding steadiness box in these PTC specimens, indicating that the upregulation of TSG101 protein is not caused by the alteration of this region. In situ hybridization analysis confirms that overexpression of TSG101 also occurs at the transcriptional level. In addition, semi-quantitative RT-PCR and subsequent Southern hybridization verify that the amounts of TSG101 transcripts are indeed lower in three normal thyroid tissues than in PTC specimens. Here we report the upregulation of TSG101 expression in PTC cells, providing the first evidence of the association of TSG101 overexpression with human tumors and suggesting that upregulation of TSG101 steady-state level might play a role in mediating tumorigenesis of human PTC.
- Published
- 2002
18. The clinical significance of gall-bladder non-visualization in cholescintigraphy of patients with choledochal cysts
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Miau-Ju Huang, Pan-Fu Kao, Yun-Fan Liaw, Kai-Yuan Tzen, and Dong-Ling You
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Male ,medicine.medical_specialty ,Time Factors ,Technetium Tc 99m Disofenin ,Scintigraphy ,Sensitivity and Specificity ,Cholecystitis ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Clinical significance ,Choledochal cysts ,Cyst ,Child ,Radionuclide Imaging ,Retrospective Studies ,medicine.diagnostic_test ,business.industry ,Imino Acids ,Gallbladder ,Technetium Tc 99m Lidofenin ,Retrospective cohort study ,Organotechnetium Compounds ,General Medicine ,medicine.disease ,Cholescintigraphy ,Choledochal Cyst ,Female ,Histopathology ,Radiology ,business - Abstract
Intravenous radionuclide cholescintigraphy (IVRC) provides a very specific picture for choledochal cysts. However, the clinical significance of the non-visualization of the gall-bladder (GB) activity in these cases is unclear. In this study, we reviewed 27 patients with choledochal cysts who underwent IVRC within 7 days prior to operation and correlated the GB findings on IVRC with the histopathological results. In 18 of the 27 patients (66.7%), there was non-visualization of the GB at 4 h post injection. Among these, two had histopathological features of acute cholecystitis (AC), 11 had chronic cholecystitis (CC), and five had normal GBs. In the other nine patients with visualization of the GB, there were five cases of CC and four normal GBs. If we apply the finding of non-visualization of the GB at 4 h post injection as the criterion for the diagnosis of AC, the diagnostic accuracy was only 40.7% (11/27). We concluded that: (1) GB disease (AC and CC) was common (66.7%: 7.4% and 59.3% respectively) in choledochal cyst patients. (2) Non-visualization of the GB on IVRC did not necessarily indicate AC in choledochal cyst cases, and the diagnostic accuracy was low. (3) GB disease is not the only cause of GB non-visualization on IVRC. A huge choledochal cyst causing a mass or reservoir effect may be a cause of GB compression and result in non-visualization of the GB.
- Published
- 1996
19. Conformational analysis and proteolytic processing of synthetic pre-pro-GnRH/GAP protein
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Saskia C. F. Milton, Jun-Ling You, Raymond Milton, Robert B. Harris, and Narasimhachar S. Rangaraju
- Subjects
Circular dichroism ,GTPase-activating protein ,Protein Conformation ,Stereochemistry ,Molecular Sequence Data ,Fluorescence Polarization ,Peptide ,Biochemistry ,Gonadotropin-Releasing Hormone ,Protein structure ,Endopeptidases ,medicine ,Denaturation (biochemistry) ,Amino Acid Sequence ,Protein Precursors ,Peptide sequence ,Protein secondary structure ,chemistry.chemical_classification ,Chemistry ,Circular Dichroism ,Hydrolysis ,GTPase-Activating Proteins ,Proteins ,Hydrogen-Ion Concentration ,Trypsin ,Protein Processing, Post-Translational ,medicine.drug - Abstract
Homogeneous pre-pro-GnRH/GAP protein was recently synthesized in 100 mg quantities by solid-phase methods and surprisingly, the synthetic pre-pro-protein, which normally does not escape the endoplasmic recticulum, was found to inhibit the release of prolactin from cultured pituitary cells. This is the first demonstration of significant biological activity associated with a precursor protein and provides the rationale for its further study. We now report the results of our initial examination of the conformational properties of pre-pro-GnRH/GAP protein as a prelude to solving its solution phase conformation by homonuclear1H-NMR protocols. Thermal andpH titration fluorescence and circular dichroism spectroscopies reveal that the protein is resistant to thermal-induced conformational changes but is particularly sensitive topH-induced conformational changes; while Asp/Glu and Arg residues may contribute to structural stability, His and Lys residues predominate. Pre-pro-GnRH/GAP is about 30% helix in the range of 2–40°C; however, even at 90°C, the peptide retains nearly 50% of its helix character. There is no evidence for a cooperative transition; for this reason, differential scanning calorimetry failed to yield a defined transition thermogram. Pre-pro-GnRH/GAP apparently does not pass through a transition state as a function of temperature but appears to flex and retain a high percentage of helix structure, resulting in subtle changes in secondary structure. There is no discernible isodichroic point. On either side of the neutralpH range, however, there are dramatic changes in structure that result in nonreversible denaturation of the protein. Relative to N(Ac)Trp-amide, the emission position of intrinsic Trp fluorescence of pre-pro-GnRH/GAP is blue shifted to 338 nm, indicating that the microenvironment(s) encompassing the 2 Trp residues are buried within the protein structure. Synthetic pre-pro-GNRH/GAP is a substrate for GAP-releasing enzyme (the proposed physiologically relevant processing enzyme of the precursor protein) and yields GAP peptide (D14–I69). Of the other serine proteinases tested (trypsin, plasmin, kallikrein), only GAP-releasing enzyme shows this specificity of cleavage. Hierarchical cleavage observed in the time course of proteolysis with trypsin, however, suggests that other peptide products might be formed from GAP once it is processed from the precursor protein by cleavage at sites other than the primary processing site catalyzed by enzymes other than GAP-releasing enzyme. The primary processing site for GAP-releasing enzyme (GLRPGGKR) is thus accessible in the precursor protein, consistent with our hypothesis that the recognition sequence is located at the surface of the protein and acts as a recognition element for the processing endoproteinase. The conformation of the precursor protein is dynamic, supporting the idea that intracellular (and/or intragranular) conditions may play a role in regulation of endoproteolysis. Conformational flexing of the pro-hormone in response to intracellular conditions may serve to differentially expose various processing sites which may help explain tissue specificity of processing.
- Published
- 1993
20. Calorimetric and spectroscopic examination of the solution phase structures of prekallikrein binding domain peptides of high molecular weight kininogen
- Author
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J. N. Scarsdale, Jun-Ling You, and Robert B. Harris
- Subjects
Circular dichroism ,Hot Temperature ,Magnetic Resonance Spectroscopy ,High-molecular-weight kininogen ,Stereochemistry ,Molecular Sequence Data ,Peptide ,Biochemistry ,Drug Stability ,Denaturation (biochemistry) ,Amino Acid Sequence ,Binding site ,chemistry.chemical_classification ,Binding Sites ,Calorimetry, Differential Scanning ,Kininogens ,Chemistry ,Circular Dichroism ,Prekallikrein ,Peptide Fragments ,Peptide Conformation ,Solutions ,Spectrometry, Fluorescence ,Thermodynamics ,Binding domain - Abstract
Unique sequence-binding sites are exposed on the surface of high molecular weight kininogen which complex prekallikrein or factor XI with high affinity and specificity. A sequence comprising 31 residues of the mature kininogen molecule (Asp565-Lys595) retains full binding activity for prekallikrein (KD = 20 nM) and assumes a complex folded structure in solution which is stabilized by long-range interactions between N- and C-terminal residues. The sequence Trp569-Lys595 (27 residues) shows only 28% of this binding affinity and lacks the key structural features required for protein recognition (Scarsdale, J. N., and Harris, R. B., J. Prot. Chem. 9, 647-659, 1990). We were thus able to predict that N- or C-terminal truncations of the binding-site sequence would disrupt the conformational integrity required for binding. Two new peptides of 20- and 22- residues have now been synthesized and their solution phase structures examined. These peptides are N- and C-terminal truncations, respectively, of the 27-residue sequence and correspond to the sequences Asp576-Lys595 and Trp569-Asp590 of high molecular weight kininogen. The results of fluorescence emission and circular dichroism (CD) spectroscopies in the range 25-90 degrees C and from differential scanning calorimetry (DSC) all substantiate the idea that the C-terminal truncation peptide binds prekallikrein 35-fold poorer than the 31-residue peptide because it is relatively unordered and possesses a less stable structure. Surprisingly, the N-terminal truncation peptide (20-mer) shows structural stability even at elevated temperatures and, like the 31-residue peptide, undergoes cold-induced denaturation observable in the DSC. 2D-NMR analysis of the 20-residue peptide revealed two distinct structures; one conformer possesses a more compact, folded structure than the other. However, the predicted structures assumed by either conformer are very different from those of either the 31- or 27-residue peptides. Hence, the binding affinity of the 20-residue peptide is 60-fold poorer than that for the 31-residue peptide because it assumes a nonproductive binding conformation(s).
- Published
- 1991
21. Synthesis, characterization and osteoconductivity properties of bone fillers based on alendronate-loaded poly(ε-caprolactone)/hydroxyapatite microspheres
- Author
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Chen, Jianhong, primary, Luo, Yun, additional, Hong, Liangqing, additional, Ling, You, additional, Pang, Jun, additional, Fang, Youqiang, additional, Wei, Kun, additional, and Gao, Xin, additional
- Published
- 2011
- Full Text
- View/download PDF
22. Cellular change and callose accumulation in zygotic embryos of Eleutherococcus senticosus caused by plasmolyzing pretreatment result in high frequency of single-cell-derived somatic embryogenesis
- Author
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Ling You, Xiang, primary, Seon Yi, Jae, additional, and Eui Choi, Yong, additional
- Published
- 2006
- Full Text
- View/download PDF
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